Surface Rust in Coolant Passages.
 

There is surface rust in the engine coolant passages in my 29 Special Coupe. The rust in the photo looks worse than it really is. I poked my finger into the holes and was able to almost wipe it off. I did not see any scaling or blocked passages in the block, and I imagine that things are okay below where I can't see.

My question is, is this something that I need to address now or should I wait and treat things after I get the head back on and things buttoned up? What would be the best way to address this?

Also, there are some minor scratches on the block. How should I addressed those?

Bill

Re: Surface Rust in Coolant Passages.
 

Flush it and forget it, not that bad

Re: Surface Rust in Coolant Passages.
 

Address it after the system is sealed, using a de-rusting product like Thermocure or Rust911. Users of this forum have reported success with both; just follow the directions.

Re: Surface Rust in Coolant Passages.
 

https://www.fordbarn.com/forum/attac...p;d=1630335751
Surface Rust in Coolant Passages.

Re: Surface Rust in Coolant Passages.
 

Turn it upside down and blow out the junk shown in the picture.

Re: Surface Rust in Coolant Passages.
 

First off, i'd get a Gano filter or similar to stop the rust chunks blocking the radiator, especially if it is a new one.

Re: Surface Rust in Coolant Passages.
 

The rust you see is normal.

Re: Surface Rust in Coolant Passages.
 

I think if you run some flex cable thru the passages you can, you’ll have more than surface rust coming out.

Re: Surface Rust in Coolant Passages.
 

Run 50/50 anti freeze and this will not happen on the future

Re: Surface Rust in Coolant Passages.
 

For sure, and it will also save many blocks from cracking during the winter months.

Re: Surface Rust in Coolant Passages.
 

Not a problem. Run anti freeze or rust inhibitor.